H9 diesel intake manifold leaks.

Inspection method for air leakage of engine intake manifold;

1. Remove the air cleaner cover and slightly increase the throttle to make the diesel engine run at a medium speed. At this point, the air pipe is blocked and air cannot enter the cylinder from the filter inlet. Observe the operation of diesel engine. If the engine speed drops rapidly within a few seconds and there is smoke in the exhaust pipe, it will automatically go out, indicating that there is no air leakage in the intake system;

2. If the engine speed drops and the exhaust pipe smokes, it can still rotate, and the self-extinguishing time is long, indicating a slight leakage;

3. If the diesel engine can continue to work, the exhaust pipe only has black smoke and cannot be extinguished by itself, indicating that the air directly enters the cylinder without being filtered, that is, the air intake system is seriously leaking.